Update t/harness to reflect behaviour changes in TAP::Harness 3.16

Explicitly add -I../lib to the switches, rather than rely on TAP::Harness or
Test::Harness picking -I../lib up from $ENV{PERL5LIB}. (Test::Harness hasn't
changed, but TAP::Harness has). Test::Harness does, however, spot that we've
altered our own @INC, and passes this on to tests. So there is no need to set
$ENV{PERL5LIB} to effect changes to @INC in tests. So don't set $ENV{PERL5LIB}
to -I../lib. Instead set it to '', to avoid contamination from our environment.

1 files changed, 7 insertions, 1 deletions

diff --git a/t/harness b/t/harness
index b087cc5b15..21d0c98ced 100644
--- a/t/harness
+++ b/t/harness
@@ -6,8 +6,8 @@
 BEGIN {
     chdir 't' if -d 't';
     @INC = '../lib';              # pick up only this build's lib
-    $ENV{PERL5LIB} = '../lib';    # so children will see it too
 }
+delete $ENV{PERL5LIB};
 
 my $torture; # torture testing?
 
@@ -244,6 +244,12 @@ if ($jobs) {
 		     }
 		    );
     }
+    $h->callback(
+		 parser_args => sub {
+		     my ( $args, $test ) = @_;
+		     push @{ $args->{switches} }, '-I../lib';
+		 }
+		);
     $h->runtests(@tests);
 } else {
     Test::Harness::runtests @tests;